The structural integrity of a vessel hull is an important safety and economical concern. For example, frictional resistance due to buildup on or fouling of the hull by algae, sea grass, barnacles, and the like as a vessel moves through the water can significantly increase the fuel consumption of the vessel. As an example, an added resistance of 30% due to moderate bio-fouling of a tanker hull can increase the fuel consumption of the vessel by up to twelve tons per day. The result is added cost to operate the vessel, as well as increased emissions. Moreover, monitoring of the hull to detect damage is useful in determining when and where repairs should be made.
A variety of methods are currently employed to reduce the likelihood of bio-fouling, and/or to monitor the structural integrity of the hull. For example, typically, while the ship is dockside and/or during normal unlading conditions, the hull can be periodically inspected manually, such as by scuba divers using various equipment. The cost of such an inspection procedure can be costly. This type of inspection effort is also typically repeated at a predetermined rate, such as every ten to twenty months or sooner, particularly if there is suspicion of damage to the vessel hull. To properly inspect the vessel hull, the hull often must first be cleaned. As a complication, however, some jurisdictions have made dockside cleaning illegal due to the release of contaminates into the water, and particularly particles of anti-fouling paint which is toxic, and which has been found to contaminate the water.